This application, "Development of the PediaFlow" Pediatric Ventricular Assist Device" is meant to address the Broad Challenge Area (04), Clinical Research, and specific Challenge Topic 04-HD-102, Development of Pediatric Medical Devices. The focus of the project is the continued development of a fully implantable, magnetically levitated, miniaturized pediatric ventricular assist device (VAD) - the PediaFlow - that will serve as bridge to transplant or bridge to recovery for the 3-20kg pediatric heart failure patients, whom, to date, are unable to be supported by conventional adult-sized ventricular assist devices and must rely instead on investigational VAD devices or extracorporeal membrane oxygenator (ECMO) technology despite its significant risk of complications and death. To that end, we have developed what we believe to be the world's smallest magnetically levitated (maglev) blood pump. The PediaFlow is exceptionally small, due to our supercritical (above resonance frequency) rotordynamic technology and valveless turbodynamic design with only one moving part. Because of our use of maglev technology, streamlined single-flowpath design, and computer- optimization design process, the PediaFlow VAD has already demonstrated unparalleled biocompatibility in pre-clinical testing of our first two prototypes. We have recently completed the design and initial production of our third prototype, which is approximately the size of a AA cell battery. Continued production, testing, and validation of this prototype, which is the focus of the work proposed herein, will bring us to the point of application to the FDA for Investigational Device Exemption (IDE) status and our first clinical trials. To achieve this goal, we will optimize and freeze the design of our third PediaFlow (PF3) pediatric VAD prototype through in-vitro and in-vivo testing, leading to our clinical version of the PediaFlow VAD design. As part of this process, we will also develop the flow estimation and physiologic control algorithm for the PediaFlow pump, as well as adapt the external electronics software and related accessories developed by our corporate partner, World Heart, Inc, for use in our PediaFlow VAD system. Accomplishing these tasks will ultimately yield a fully integrated PediaFlow system for clinical use. PUBLIC HEALTH RELEVANCE: The aim of this project is to complete the design and validation of a fully implantable, magnetically levitated left ventricular assist device for infants and children. We propose a series of laboratory and animal studies which will demonstrate the superior biocompatibility and hemodynamic performance of our pediatric ventricular assist device. The results of these studies will lead to a design freeze in anticipation of submitting an application to the FDA for Investigational Device Exemption.